1. Field
Aspects of the present invention generally relate to a mechanism for locking a circuit breaker and more specifically relates to a key locking device or an accessory that prevents circumvention of a locking feature and selectively provides an ability to lock in an ON state of the circuit breaker.
2. Description of the Related Art
Locking of circuit breakers is essential to protect property and life from electrical hazards. Locking of a circuit breaker allows a user to prevent the circuit breaker from being switched from OFF to ON or vice-versa by some other unauthorized person. Locking the circuit breaker is typically done by blocking the movement of a handle on the exterior of the circuit breaker housing, usually with some type of assembly that employs a pad lock.
Among other things, a circuit breaker may include a circuit breaker accessory pocket, a tripping mechanism and contacts. A cylinder lock mechanism that resides in a circuit breaker accessory pocket is also used to actuate a tripping mechanism of a circuit breaker. “Locking” the circuit breaker forces the circuit breaker into the “tripped” state causing the contacts to open if they are closed at the time of “locking” and preventing the operating mechanism from acting on the contacts to close them.
However, circumvention of a locking feature via disassembly can allow an unauthorized person to gain access to the switching functionality of a locked circuit breaker. Circuit breaker locking is generally intended to provide the ability to lock the breaker only in the OFF state. Because of the safety implications of locking a circuit breaker in the ON state, an ability to lock the circuit breaker in the ON state is generally not provided. Although under some circumstances an ability to safely lock the circuit breaker in the ON state may be needed.
Therefore, there is a need for improvements in locking mechanisms for locking a circuit breaker.